xref: /freebsd/share/man/man9/pmap_qenter.9 (revision fa9896e082a1046ff4fbc75fcba4d18d1f2efc19)
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26.Dd February 15, 2018
27.Dt PMAP_QENTER 9
28.Os
29.Sh NAME
30.Nm pmap_qenter ,
31.Nm pmap_qremove
32.Nd manage temporary kernel space mappings
33.Sh SYNOPSIS
34.In sys/param.h
35.In vm/vm.h
36.In vm/pmap.h
37.Ft void
38.Fn pmap_qenter "vm_offset_t sva" "vm_page_t *m" "int count"
39.Ft void
40.Fn pmap_qremove "vm_offset_t sva" "int count"
41.Sh DESCRIPTION
42The
43.Fn pmap_qenter
44function accepts a linear array of
45.Fa count
46pointers to wired pages
47.Fa *m ,
48and enters each of these pages into the kernel virtual address (KVA) space,
49beginning at the address
50.Fa sva .
51The pages are mapped non-executable, if possible.
52(For example, non-PAE i386 has no capability to map pages non-executable.)
53.Pp
54The
55.Fn pmap_qremove
56function tears out a mapping from the kernel virtual address space,
57beginning at
58.Fa sva
59and for
60.Fa count
61pages.
62.Sh IMPLEMENTATION NOTES
63The
64.Fn pmap_qenter
65function is intended for temporary mappings that do not require page
66modification or reference counting.
67Old mappings are simply overwritten.
68The pages
69.Em must
70be wired into physical memory.
71.Pp
72The corresponding
73.Fn pmap_qremove
74function is intended to remove such temporary mappings.
75.Sh SEE ALSO
76.Xr pmap 9
77.Sh AUTHORS
78This manual page was written by
79.An Bruce M Simpson Aq Mt bms@spc.org .
80